WHEN I WAS A KID, my mother worked for a long time for a Catholic hospital administered by a wonderful old nun. She had been at the hospital for years and years, a fine administrator -- a sweet and loving woman. One day she was transferred to a teaching position. She left smiling.

This memory comes to me now because I have been thinking of Father Robert Drinan, the congressman-priest who has been ordered by the Vatican not to seek reelection. Like the old nun he had been told that what he has been doing -- and doing well -- he must no longer do. He will leave, maybe not smiling, but he will leave.

Drinan was not your basis soft-hearted, emotional, brogue-talking Grade B movie priest. He could get irate. He was irate, for instance, at the House Un-American Activities Committee -- that obscenity that could have turned itself inside out before it could even define what an un-American activity is. iDrinan got irate about the war in Vietnam and later he got irate at Richard Nixon. He was the first to call for the president's impeachment. It was not, with Drinan, a political act. Nixon, it seemed, simply offended him. He found the man and his actions repugnant -- immoral. How refershing!

So it is sad to see him go. It is also confusing. One treads cautiously when writing about someone else's religion, but I, for one, don't get it. I understand what Pope John Paul II has said about priests and politics -- how they should be ministers and not politicians and I have to admit there is some logic to what he says. But I don't see how a law school dean, which is what Drinan was before he went to Congress, makes a "minister" out of him anymore than I understand why the order applies to elected officials, but not, apparently, appointed ones.

In fact, I have the vague suspicion that Drinan would not have received the papal pink slip if he and the other priests engaged worldwide in politics had not come down on the liberal side of most issues. The pope is, to say the least, no liberal. He is, in fact, a conservative man and since becoming pope he has issued injunctions against priests getting involved in politics, choosing Central America (Mexico) for his first pronouncement, a place where priests have been on the cutting edge of social reform. When the liberal archbishop of El Salvador, Oscar Romero, was gunned down while saying mass, the pope's outrage was so muted that it was taken as a political statement of its own.

In fact, you could argue that politics is itself a ministry, that in Latin America, particularly, once you silence the church on human rights, you have nothing but silence. It is often the only voice for reform. As for Drinan, he looked upon the House of Representatives as his parish. You could see he had his work cut out for him.

But having said all that, I am still struck at what happened: Drinan has quit politics. Here is a man -- a politician, for crying out loud -- who has conceded by deed that he is not unique, that he can be replaced, that someone else can do the job. Here is a man who can put his own ego into perspective. It is stunning. You have to understand: I have been living in Washington for a long time.

But there is something else to be said about Drinan. He was just the sort of politician some people single out as some sort of brat -- what used to be called a peacenik. Someone -- Agnew, for sure -- would lump him in with all the others and then throw the whole mix up into the air like pizza dough, shove it into the oven and what comes out could be called the Me Generation.

But here is the antithesis of "me". Here is a man who puts his ego and his ambition and even, I suspect, his personal sense of where he can do the most good, and subsumes it all into something bigger -- the Catholic Church and all it means to him. Here is a man with the rarest of gifts -- a sense of himself and where he fits into things. Like the old nun who had administered a hospital, he knows for himself what is important and less important and least important of all. He leaves Washington as he came, teaching his lessons by example, leaving me, for one, a bit sad but also envious.

Now I know why that old nun was smiling.